화학공학소재연구정보센터
Journal of Chemical and Engineering Data, Vol.59, No.11, 3863-3872, 2014
Construction of Aqueous Two-Phase Systems of the Cyclopolymer of (Diallylamino)propylphosphonate and Its Sulfur Dioxide Copolymer with Polyoxyethylene Using H-1 NMR Spectroscopy
A pH-responsive polyzwitterionic acid [PZA)], poly[3-(N,N-diallylammonio)propanephosphonic acid], and an alternate copolymer PZA center dot c, poly[3-(N,N-diallylammonio)propanephosphonic acid-alt-SO2] have been prepared via cypolymerization. Aqueous two phase systems (ATPSs) of polyoxyethylene (POE)(NaOH-treated PZA or PZA center dot SO2)water (NaCl) have been investigated. To construct the tie lines, the compositions of the phases were determined by H-1 NMR spectroscopy. The addition of 1, 1.5, and 2 equiv NaOH transform the (+/-) zwitterionic polymers to their corresponding (+/--) zwitterionicanionic, (+/--)/(=) zwitterionicanionic/dianionic, and (=) dianionic polyelectrolyte. The influence of NaOH and salt (NaCl) on the binodals have been examined. Increasing the amount of added NaOH pushes the binodals toward lower concentrations, thereby requiring a lesser amount of polymers for phase separation. The NH+ and the OH functional groups in (+/-) PZA and (+/-) PZA center dot SO2 provide the required motifs for the base-induced change of the charge densities in the macromolecule, whose size and shape can thus be manipulated to facilitate potential separation of proteins in the ATPSs. A combined total mass fraction of less than 0.10 for the component polymers makes these ATPSs viable for industrial applications. The water-insolubility of PZA center dot SO2 at lower pH values makes it a suitable component for recycling ATPS.